Examples of energy transferring systems are plentiful. For example, it is well-known in the art to utilize mechanical slip rings for transferring electrical current from a rotating body to a nonrotating body. Conventionally, a conducting ring on one body is physically contacted by one or more conducting brushes on the other body allowing current to flow between the bodies. This type of mechanical arrangement is subject to wear and self-generating electrical noise which may obscure the signal being transmitted.
More recently, optical slip rings, exemplified by U.S. Pat. No. 4,027,945, issued June 7, 1977, to Iverson, have been disclosed, whereby signals may be transferred from a rotating body to a nonrotating body without any physical contact. In Iverson, fiber optic bundles are utilized to conduct light signals across a small gap from a rotating body to separate fiber bundles located on the other body.
The system of Iverson and others representative of the art suffer from certain disadvantages, i.e., that (1) light may not be extracted anywhere but must be extracted at particular points, (2) a precise optical path is usually required, and (3) the systems are complicated in construction and relatively inflexible in design.